Comparison of Enterococcus density estimates in marine beach and bay samples by real-time polymerase chain reaction, membrane filtration and defined substrate testing

► qPCR shows promise as a beach monitoring tool and can provide results in 4 h. ► Strong correlation between qPCR results and conventional enterococci methods. ► Regression equation is y = 1.0x + 13.3, where y = qPCR; x = MF/Enterolert results.